Index for Section 3

Alphabetical listing for I

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ilogb(3)
NAME
  ilogb - Returns an unbiased exponent

SYNOPSIS
  #include <math.h>

  int ilogb(
	  double x );

  int ilogbf(
	  float x );

  int ilogbl(
	  long double x );

LIBRARY
  Math Library (libm)

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  ilogb():  XPG4-UNIX

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

DESCRIPTION
  The ilogb(), ilogbf(), and ilogbl() functions return the integral part of
  the base r logarithm of (|x|) as a signed integral value for non-zero x,
  where r is the radix of the machine's floating point arithmetic.

  The following table describes function behavior in response to exceptional
  arguments:

  ______________________________________________________________________
  Function			 Exceptional Argument	Routine Behavior
  ______________________________________________________________________
				 |x| = infinity		INT_MAX

  ilogb(), ilogbf(), ilogbl()
				 x = 0, NaN		INT_MIN

  ilogb(), ilogbf(), ilogbl()
  ______________________________________________________________________

Index for Section 3

Alphabetical listing for I

Top of page